Speed limits along any given route may change frequently, particularly in urban settings, as a driver drives through various areas. Moreover, even along a given route speed limits may change at certain times, such as during school hours or "rush-hours." The current and accepted method of informing the driver of the speed limit is to post speed limit signs on the side of the road. This presents a problem if the driver cannot see, or does not notice, one or more of these signs.
The drivers field of vision can be blocked or obscured in a number of ways. Common causes include: (i) larger vehicles or trees, (ii) poor lighting conditions, (iii) damaged, missing, or vandalized signs, and (iv) weather, such as snow, accumulating on signs, on windows, or merely obstructing the view while falling. Additionally, the driver might not be able to look to the side of the road because of busy traffic conditions.
Accordingly, there is a need for a system of communicating speed limits to the driver which overcomes the above problems.